Probably about the same as their Legends counterparts, since they can take control of ships and resources to do their job. Although the Legends ones are probably a little better, since they could take entire fleets.

__________________"It didn't matter what they'd been before. All that mattered was that they were willing to fight—and maybe die—for the Alliance."―Col Serra.

Vader is called "Palpatine's right hand man" in the R1 novelisation for what that's worth. I'd say going by that and the novel Tarkin, that Vader and Tarkin's positions are likely interchangeable depending on circumstances.